Telogen effluvium

Telogen effluvium is the name for hair loss due to shedding of excessive numbers of resting or telogen hair. New hair continues to grow. Telogen effluvium can be acute (single episode i.e. temporary shedding) or chronic (persistent shedding over a long period of time). Although the loss of excessive amounts of hair during telogen effluvium may reduce the overall bulk of the hair, it does not result in baldness.

It should be distinguished from anagen effluvium, in which hair shedding is due to interruption of active or anagen hair growth by drugs (e.g. chemotherapy), toxins or inflammation (e.g. alopecia areata), which can cause baldness.

Telogen effluvium

Normal hair loss

In a normal healthy person's scalp about 85% of the hair follicles are actively growing hair (anagen hair) and 15% are resting hair (telogen hair). Anagen hair has a pointed or tapered tip. Telogen hair has a bulb or club-shaped tip.

A hair follicle usually grows anagen hair for 4 years or so, then rests for about 4 months. A new anagen hair begins to grow under the resting telogen hair and pushes it out. Thus, it is normal to lose up to about 100 hairs a day on one's comb, brush, in the basin or on the pillow, as a result of the normal scalp hair cycle. Most of these are bulb hairs with a club-shaped tip.

Acute telogen effluvium

Acute telogen effluvium usually follows some shock to the system, when as many as 70% of the anagen hairs can be precipitated into telogen. Typical precipitants include:

Illness, especially if there is fever
Surgical operation
Accident
Childbirth
Nervous shock
Weight loss or unusual diet
Certain medications
Discontinuing the contraceptive pill
Overseas travel resulting in jetlag
Excessive sun exposure

The resting hairs remain firmly attached to the hair follicles at first. About 2 months after the shock, new hairs coming up through the scalp push out the telgoen hairs and increased hair fall is noticed.

Thus, paradoxically, with this type of hair loss, hair fall is a sign of hair regrowth. As the new hair first comes up through the scalp and pushes out the dead hair a fine fringe of new hair is often evident along the forehead hairline. At first the fall of club hairs is profuse and a general thinning of the scalp hair may become evident, but after several months a peak is reached and hair fall begins to lessen, gradually tapering back to normal over 6-9 months. As the hair fall tapers off the scalp thickens back up to normal, but recovery may be incomplete in some cases.

Beau line

A Beau line is a groove across one or more nails that may accompany acute telogen effluvium. Nail and hair growth are under the same influences. The time of the precipitating shock to the system can be estimated from the fact that a finger nail takes about 5 months to grow from the posterior nail fold to the free edge. So if the groove in the nail is half way down the nail then the shock must have been 2½ months ago.

Beau line
	Transverse leukonychia

Chronic telogen effluvium

In chronic telogen effluvium, there is persistent or cyclical diffuse hair loss and inability to grow the hair long. The hair cycle is reset with a shortened anagen period.

Chronic telogen effluvium does not alter the overall thickness of the hair. In fact, shedding tends to be more noticeable in those with thick, long hair – this is because they notice it more than those with shorter, finer hair.

There are often fluctuations in severity (cyclical diffuse hair shedding) reminiscent of moulting in other mammals.

Telogen effluvium does not cause baldness, although it may unmask a genetic tendency to genetic balding i.e. female pattern hair loss , or in men, male pattern hair loss. Thus, bi-temporal recession is common (high forehead).

Should any tests be done?

In diffuse hair loss, tests are often done to exclude thyroid disease or iron deficiency, as these may also cause hair thinning. Occasionally, biopsy may be performed.

What is the treatment for telogen effluvium?

Acute telogen effluvium is self-correcting. It is really not influenced by any treatment that can be given. However, gentle handling of the hair, avoiding over-vigorous combing, brushing and any type of scalp massage are important. No specific diets are necessary.

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